Device and Method for Endoluminal Therapy

ABSTRACT

A device and method for selectively engaging or penetrating a layer of a luminal organ wall where the luminal organ wall has a plurality of layers including an outermost layer and an innermost layer adjacent to the lumen of the organ. The device and method select one of the plurality of layers of the organ wall other than the innermost layer and deploy from within the lumen of the organ a tissue device through the innermost layer to a specific depth to engage or penetrate the selected one of the plurality of layers. The device and method may be employed to create luminal pouches or restrictive outlets. In a stomach organ, the device and methods may be employed to treat obesity by forming a gastric pouch with or without a restrictive outlet.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a divisional application and claims thebenefit of priority of U.S. application Ser. No. 10/659,211, entitled“Device and Method for Endoluminal Therapy”, filed on Sep. 9, 2003,Attorney Docket END01US and claims the benefit of priority ofProvisional Patent Application 60/409,838, entitled “Method andApparatus for Treating Obesity”, filed on Sep. 9, 2002, Attorney DocketBKELL.002PR, the entirety of each is incorporated by reference.

BACKGROUND

1. Field of the Invention

The invention relates to endoluminal therapy, and, in particular, tomethods and devices for securement of hollow organs, including gastricrestriction procedures in the stomach for treating obesity andgastroesophageal reflux disease (GERD).

2. Description of the Related Art

Flexible endoscopic therapy of the hollow organs such as the stomach,intestines and esophagus has been shown to have fewer complications andfaster recovery times than traditional or laparoscopic surgery. As such,there is a growing interest in expanding the capabilities of suchtherapy. In particular, there is a desire to perform organ modification,for example gastroplasty, from within the lumen of the organ through atrans-luminal route using flexible endoscopic tools.

Until now, there have been no practical devices available to enableprocedures such as endoluminal plasty in a safe and reliable manner. Themost challenging part of such a procedure is the placement of durablesecurement elements, such as sutures, through the full thickness of theorgan walls in order to secure portions of the organ together or toattach elements to the wall. The reason securement element placement ischallenging is that the organ wall may consist of multiple layers, eachhaving unique physical properties. For example, the stomach has threeprimary wall layers including an innermost layer is the mucosa, themiddle layer is the muscularis, and the outermost layer is the serosa.The mucosa is a relatively fragile layer and is loosely connected to themuscularis. The mucosa typically comprises a plurality of folds, calledrugal folds, or rugae, which make the thickness of the mucosal layerhighly variable and unpredictable. Securement elements anchored in themucosa have been shown to pull out over time. The muscularis is somewhattougher; although securement elements placed there may still pull outover time if they are placed under tension, as is the case forgastroplasty. In the stomach, the serosa layer is thin but is thetoughest of the three layers. It is believed that to create durablesecurement of the stomach wall, securement elements need to pass throughthe serosa. This presents a challenge for endoluminal therapy, however,since the combined thickness of the three layers of the stomach wall isnormally unpredictable.

In order to deploy a securement element that consistently passes throughan ideal layer of an organ wall, the length of the securement element orthe depth of deployment needs accurately engage the desired layer. Whenthe desired layer of a wall is the outermost layer, surroundingstructures may be in danger of being engaged by such securement elementor deployment device.

There is therefore a need for devices and methods to safely and reliablydeploy securement mechanisms to a desired layer of the organ wallwithout endangering surrounding structures.

Another challenge of endoluminal devices intended for use in organtherapy is the engagement and movement of regions of the organ wall inorder to approximate and secure multiple locations. Existing endoscopictools for grabbing, such as grasping forceps, tend to engage only theinnermost layer, the mucosa in an exemplary organ, the stomach. It mayrequire a significant amount of force to move a region of the organwall, pulling by the innermost layer may tear it. A more reliable methodof moving the wall is to engage other layers. Further, the process ofapproximating two regions of the wall may require multiple instruments.

There is, therefore, a need for methods and devices to approximatemultiple regions of the wall within a hollow organ, and specifically toselectively engage the muscularis within the stomach wall. There is afurther need for instruments that combine the above steps of engaging,approximating and securing multiple regions of the wall of a holloworgan, such instruments being further refined to enable a specificendoluminal procedure such as gastroplasty.

In an organ, it may be desirable to modify the flow rate or pressure ofmaterials or fluids that propagate through the organ's lumen.

There is thus a need for methods and devices to create a restrictiveoutlet to a luminal pouch from within the lumen of the organ.

Organ wall approximation and restrictive outlet performance may diminishover time as the organ wall dilates due to luminal pressure.

There is, therefore, a need for methods and devices to reduce the amountof permanent dilation that an organ wall undergoes followingmodification procedures.

SUMMARY

The preferred methods and devices described herein provide for advancedendoluminal procedures involving hollow organs. Such advanced proceduresinvolve selective engagement of a target layer within the wall of ahollow organ, approximation of multiple regions of the wall, and safeand reliable placement of securement elements through the full thicknessof the wall without endangering structures surrounding the hollow organ.Specific methods and devices described enable endoluminal proceduressuch as gastroplasty for the treatment of obesity and GERD, involvingthe formation of a gastric pouch or partition and a restrictive outlet.Further methods and devices provide for minimizing the dilation of thepouch or restrictive outlet over time.

In one of more preferred embodiments of the invention, devices andmethods are described for selectively engaging a target layer within thewall of a hollow organ. In one exemplary embodiments, the innermost walllayer of an organ is manipulated to flatten out the folds and therebymake the depth required to reach an inner layer more predictable. Theflattening may be done by insufflation, or by stretching or pressing outthe folds. Either during or after the flattening of the innermost walllayer, a tissue engagement mechanism or tissue penetration element maybe brought into close contact with the innermost wall layer and thetissue mechanism or element may be deployed to a specific depth, whichmay be adjustable. In one or more additional embodiments, an electricalimpedance measurement system may be employed to measure the impedance ofan organ wall at various depths, in order to provide data on thethickness of various layers prior to deployment of the mechanism orelement, or to provide feedback regarding actual progress of themechanism or element as it moves through the layers of the wall. In thelatter embodiments, the tissue-penetrating element may be part of theimpedance measurement system and may incorporate a tissue securementelement, and the target depth of deployment may range from an innerlayer, such as the muscularis of a stomach, to the full thickness of thewall.

In one or more additional preferred embodiments, methods and devices aredisclosed for safely and reliably penetrating or securing the wall of ahollow organ without endangering surrounding structures. In one seriesof embodiments, methods and devices are described wherein the wall ofthe hollow organ is engaged and pulled into its lumen in order to createa safety gap between the outer surface of the organ and surroundingstructures, and a tissue device such as a tissue penetrating element orsecuring element is deployed to safely penetrate the wall withoutextending beyond the safety gap. In an additional series of preferredembodiments, electrical impedance may be used to guide the deployment ofthe tissue-penetrating element, with or without creation of a safetygap. In the case where a safety gap is not created, the tissue impedancemeasurement system may be configured to provide feedback when the tip ofthe tissue penetrating element has passed through the outermost walllayer, thereby allowing the operator, or an automatic deployment system,to stop further deployment. In at least one preferred embodiment of theaforementioned methods and devices for safely and reliably penetratingthe wall of a hollow organ are applied to a stomach where the methodsmanipulate the mucosa prior to deployment of a tissue-penetratingelement or securement mechanism to improve the predictability of theoverall thickness of the stomach wall. In a further preferredembodiment, the methods and devices described may be used to pass notonly a securement device through the wall, but also devices such aselectrodes, anchoring devices, implantable devices, or conduits forfluids, materials or other devices.

In yet another group of preferred embodiments of the invention, methodsand devices are described for approximating two or more regions of awall of a hollow organ. In at least one preferred embodiment for astomach organ, the muscularis wall layer is selectively engaged in twoor more regions using the methods and devices described previously, andthen the regions are pulled together. In another preferred embodiment,the walls are pulled into the lumen to create a safety gap to allow safeand reliable deployment of securement elements through the wall wherethe securement elements are then pulled together to approximate theregions. In another embodiment, the walls are approximated and thenpulled into the lumen to create a safety gap prior to deployment of asecurement element through both regions of the wall.

Other preferred embodiments of the present invention relate to methodsand devices for performing gastroplasty procedures. Specific methods anddevices are described for safe and reliable engagement, approximationand securement of regions of the stomach wall to create a gastric pouchor partition, using combinations of the methods and devices describedpreviously. In at least one embodiment, methods and devices aredisclosed for performing endoluminal gastroplasty using a deviceconfigured to pass through the esophagus and enable the steps ofengagement, approximation and securement of the anterior and posteriorwalls of the stomach to create a gastric partition. In at least oneembodiment of the aforementioned methods and devices, the devicecomprises a pair of hinged effectors, each of which is configured tomanipulate the mucosa, the innermost wall layer in an exemplary organ,the stomach and selectively engage the muscularis, the next wall layerin the exemplary organ, the stomach at two regions of the wall, and thenapproximate the two regions and safely and reliably deploy afull-thickness securement element through the two regions. In onevariant of this embodiment, a biocompatible material may be used toreinforce the sites of securement of the approximated regions of thewall. In a specific method for using the aforementioned device to createa more substantial gastric pouch with a small restrictive outlet todelay the passage of material or fluid through the organ's lumen, thedevice is used to create a first partition and then a second partitionadjacent to the first. In another group of related preferredembodiments, a device is described which incorporates a stitchingmechanism, and methods are disclosed for using this device to create aluminal partition or pouch, with or without a restrictive outlet. Afurther preferred embodiment describes a method of combining thehinged-effector device with the stitching device to create a luminalpouch with a restrictive outlet.

In another preferred embodiment of the invention, a device is disclosedwhich employs a biocompatible material for attachment between theanterior and posterior walls of an organ to create a partition, whichmay be useful in the treatment of obesity or GERD in a stomach organ,and which may or may not incorporate a restrictive outlet. A method isalso described for attaching the biocompatible material to the organwall.

In another series of preferred embodiments, methods and devices aredescribed for creating an effective and durable restrictive outlet to aluminal pouch, in order to delay/restrict flow through the luminalpouch, as is desired in the case of an anti-obesity procedure, or torestrict the reflux of a stomach's contents from the pouch, as isdesired in the case of a GERD treatment. In one preferred embodiment, amethod and device are disclosed for gathering and bunching togetherexcess innermost wall layer segments in the vicinity of the desiredoutlet, and securing the bunched layer segments so as to at leastpartially block the flow of material or fluid through the outlet. Inanother series of preferred embodiments, an object is attached to theorgan wall to create a restrictive outlet, which may be adjustable. Inyet another embodiment, a method is disclosed for bulking the region ofa luminal pouch outlet so as to create a restriction. In one or moreadditional preferred embodiments, methods and devices are describe forforming a tubular extension of the luminal pouch so as to create arestriction to flow, wherein the restrictive effect may be increased ordecreased by lengthening or shortening the extension, respectively, orby adding or removing pleats along the length of the extension, all ofwhich may be done endoscopically to adjust the restrictive effect asdesired. In still another preferred embodiment, methods and devices aredisclosed for forming a restrictive outlet to a luminal pouch bymodifying the properties of the organ wall tissue in the vicinity of thedesired outlet.

In another group of preferred embodiments, methods are disclosed fortreating the walls of the stomach in the vicinity of a gastric pouch andrestrictive outlet to minimize the amount of dilation that may occur.Such methods include modifying the properties of the stomach wall so asto create scarification or shrinkage of the tissue layers.

For purposes of summarizing the preferred embodiments of the inventionand the advantages achieved over the prior art, certain objects andadvantages have been described herein above. Of course, it is to beunderstood that not necessarily all such objects or advantages may beachieved in accordance with any particular embodiment of the invention.Thus, for example, those skilled in the art will recognize that theinvention may be embodied or carried out in a manner that achieves oroptimizes one advantage or group of advantages as taught herein withoutnecessarily achieving other objects or advantages as may be taught orsuggested herein.

All of these embodiments are intended to be within the scope of thepresent invention herein disclosed. These and other embodiments of thepresent invention will become readily apparent to those skilled in theart from the following detailed description of the preferred embodimentshaving reference to the attached figures. The invention is not limitedto any particular preferred embodiment(s) disclosed.

BRIEF DESCRIPTION OF DRAWINGS

Having thus summarized the general nature of the invention, certainpreferred embodiments and modifications thereof will become apparent tothose skilled in the art from the detailed description herein havingreference to the figures that follow, of which:

FIG. 1 is an anterior schematic view of an exemplary luminal organ, astomach;

FIG. 2 is a section view of the stomach wall taken through line 2-2 ofFIG. 1;

FIG. 3 is a section view of the stomach and surrounding anatomy takenthrough line 3-3 of FIG. 1;

FIGS. 4 a-b are section views illustrating the steps of for manipulatingthe mucosal surface of the stomach;

FIGS. 5 a-b are section views illustrating the steps of selectivelyengaging the muscularis of the stomach;

FIGS. 6 a-b are section views illustrating the steps of pulling thestomach wall into the lumen of the stomach and creating a gap betweenthe stomach wall and surrounding anatomy;

FIGS. 7 a-b are section views illustrating the deployment of securementdevices through the stomach wall into the safety gap, with 7 a showing acurved suture and 7 b showing a hollow needle deploying a T-anchor.

FIG. 8 is a schematic illustration of a trans-esophageal device beinginserted into a patient's stomach;

FIG. 9 is a perspective view of a trans-esophageal device configured tosecure two regions of the stomach wall together;

FIG. 10 is a schematic view of another aspect of the device of FIG. 9;

FIG. 11 is a schematic view of another aspect of the device of FIG. 9;

FIG. 11 a is an enlarged view of a portion of the device of FIG. 9 atline 9 a;

FIG. 12 is a schematic illustration of an arrangement of the mechanismswithin the device of FIG. 9;

FIG. 13 is a section view taken through line A-A of FIG. 8 demonstratinginitial positioning of the device of FIG. 9 within the lumen of thestomach;

FIG. 13 a is an enlarged view of one of the hook needles, showing itsslightly retracted and un-deployed position in the configuration of thedevice as shown in FIG. 13;

FIG. 14 is a section view taken through line A-A of FIG. 8 demonstratingthe device in relation to the lumen of the stomach after the lumen hasbeen evacuated;

FIG. 14 a is an enlarged view of one of the hook needles, showing itsslightly retracted and un-deployed position in the configuration of thedevice as shown in FIG. 14;

FIG. 15 is a section view taken through line A-A of FIG. 8 demonstratingthe opening of the device and engagement of the mucosa;

FIG. 15 a is an enlarged view of one of the hook needles, showing itsslightly retracted and deployed position in the configuration of thedevice as shown in FIG. 15;

FIG. 16 is a section view taken through line A-A of FIG. 8 demonstratingclosing of the device to stretch out the mucosa around the body of thedevice;

FIG. 16 a is an enlarged view of one of the hook needles, showing itsslightly retracted and deployed position in the configuration of thedevice as shown in FIG. 16;

FIG. 17 is a section view taken through line A-A of FIG. 8 demonstratingthe opening of the device and engagement of the muscularis;

FIGS. 17 a-b show an enlarged view of one of the hook needles, showingin 17 a its un-retracted and un-deployed position, and in 17 b itsun-retracted and deployed position as shown in FIG. 17;

FIG. 18 is a section view taken through line A-A of FIG. 8 demonstratingretraction of the engaged walls into the lumen of the stomach;

FIGS. 18 a is an enlarged view of one of the hook needles, showing itsfully retracted and deployed position in the configuration of the deviceas shown in FIG. 18;

FIG. 19 is a section view taken through line A-A of FIG. 8 demonstratingclosure of the device to approximate the engaged regions of the wall;

FIG. 20 is a section view taken through line A-A of FIG. 8 demonstratingadvancement of a securement element through the approximated walls ofthe stomach;

FIG. 21 is a section view taken through line A-A of FIG. 8 demonstratingthe securement element in place through the approximated walls of thestomach;

FIG. 22 is an anterior schematic view of a stomach after the proceduredemonstrated in FIGS. 13-21 is complete;

FIG. 22 a is a section view of the stomach shown in FIG. 22, takenthrough line 22 a-22 a;

FIG. 23 is a cutaway view of the stomach, showing positioning of thedevice of FIG. 9 for creating a gastric partition;

FIG. 24 is a schematic view of the stomach of FIG. 23, showing theresulting position of the gastric partition;

FIG. 25 is a cutaway view of the stomach, showing positioning of thedevice of FIG. 9 for creating a second gastric partition;

FIG. 26 is a schematic view of the stomach of FIG. 25, showing theresulting position of the second gastric partition, and the resultingpouch formed by the two partitions;

FIG. 27 is a cutaway view of the stomach showing an endoscopic devicefor modifying the walls of the gastric pouch;

FIG. 28 is a cutaway view of a stomach that has been modified per theprocedure shown in FIGS. 13-21, with the addition of reinforcingmaterial;

FIG. 29 is an anterior schematic view of a stomach, showing the positionof a gastric partition created by attachment of a section ofbiocompatible material;

FIG. 29 a is a section view taken along line 29 a-29 a in FIG. 29showing the securement of the biocompatible material between theanterior and posterior walls of the stomach;

FIG. 30 is a perspective view of a suture deployment device, shownattached to the end of a flexible endoscope;

FIG. 31 is a section view of the suture deployment device of FIG. 30,showing the needle deployment arm ready to push the needle;

FIG. 31 a is a detail view of a needle useful in a suture deploymentdevice;

FIG. 32 is a section view of the suture deployment device of FIG. 30,showing the needle deployed;

FIG. 33 is a section view of the suture deployment device of FIG. 30,showing the needle deployment arm ready to retract the needle;

FIG. 33 a is a section view of a variant of the suture deployment deviceof FIG. 30, showing an adjustable horizontal surface on the face of thedevice to control the depth of needle deployment;

FIG. 34 is a section view of the suture deployment device of FIG. 30,showing the needle retracted;

FIG. 35 is a side section view showing actuating mechanisms useful in asuture deployment device;

FIG. 36 is a top section view of the actuating mechanisms of FIG. 17taken through line 18-18;

FIG. 37 is a perspective view of a different suture deployment devicehaving mucosal stretching and muscularis engagement mechanisms;

FIG. 38 is a perspective view of the suture deployment device of FIG. 30having tissue engagement mechanisms;

FIG. 39 is a side section view of the suture deployment device of FIG.38;

FIG. 40 is a block diagram of a tissue impedance measurement system;

FIGS. 40 a and 40 b show graphs of tissue impedance at various locationsin and around the wall of a hollow organ;

FIG. 41 is a side section view showing a suture deployment deviceadapted to measure tissue impedance;

FIG. 42 is a perspective view of a hollow needle adapted to measuretissue impedance;

FIG. 43 is an anterior schematic view of a stomach which has undergone agastric restriction procedure including an elongated restrictive outlethaving a length L and diameter D;

FIG. 44 is a cutaway view of a stomach which has undergone the gastricpartition procedure shown in FIG. 22, with an endoscopic device shownfor the creation of a restrictive outlet via mucosal bunching;

FIG. 44 a is an enlarged schematic view of the mucosal bunching deviceshown in FIG. 44;

FIGS. 45 a-j are schematics views of various devices to reinforce andaugment a restrictive outlet to a gastric pouch;

FIG. 46 is a cutaway view of a stomach which has undergone the gastricpartition procedure shown in FIG. 22, showing an endoscopic devicemodifying the stomach walls near the outlet of the gastric pouch tocreate a restriction;

FIG. 47 is a section view showing an endoscopic device configured toinvaginate and secure a fold of stomach wall;

FIG. 48 is a section view showing the endoscopic device of FIG. 47engaging the mucosa;

FIG. 49 is a section view showing the endoscopic device of FIG. 47showing the mucosa spread;

FIG. 50 is a section view showing the endoscopic device of FIG. 47 fullyopen and preparing to engage the muscularis;

FIG. 51 is a section view showing the endoscopic device of FIG. 47 shownhaving invaginated a fold of the stomach wall and deploying a securementdevice;

FIG. 52 is a section view of the stomach of FIG. 51 after deployment ofthe securement device and removal of the endoscopic device;

FIG. 53 is an anterior schematic view of a stomach that has undergonethe invagination procedure shown in FIGS. 48-52 followed by a stitchingprocedure to create a gastric partition as well as to create arestrictive outlet by trapping the invaginated fold at the outlet of thepouch.

DETAILED DESCRIPTION

The present invention relates to endoluminal therapy and particularly tomethods and devices for manipulation of the walls of luminal organs suchas the stomach. Before describing embodiments of the devices and methodsof the invention, an exemplary luminal organ, a stomach 10 will first bedescribed in more detail. It is understood that the method and devicesof the present invention may be applied to any luminal organ.Application of the present invention a stomach 10 is thus forillustrative purposes only. FIGS. 1, 2 and 3 illustrate a representationof the normal anatomy of a stomach 10.

As shown if FIG. 1, the exemplary luminal organ, the stomach 10 includesan upper opening at the esophagus 12, an Angle of His 32 at the junctionbetween esophagus 12 and stomach 10, and a lower opening at the pylorus14 which communicates with the small intestine (not shown). Forreference, the stomach 10 further includes a lesser curvature 16 and agreater curvature 18 as well as posterior and anterior stomach walls 20.This organ, the stomach wall 20 comprises three major layers (shown incross-section in FIG. 2): an outermost layer, the serosa 22, themuscularis 24 and the innermost layer, the mucosa 28. (For simplicity,sub-layers such as the sub-mucosa, muscularis propria, muscularismucosae and others have been grouped together within the appropriatemajor layers and are therefore not discussed independently.) In anormal, undistended stomach 10, the innermost layer, the mucosa 28 isloosely attached to the next wall layer, the muscularis 24 and typicallyforms numerous rugal folds or rugae 30.

FIG. 3 is a cross-section of the stomach 10 of FIG. 1 taken at line 3-3,showing typical surrounding anatomy such as the liver 500, spleen 502and splenic artery 504. The lower esophageal sphincter 506 has also beenshown to provide perspective.

The deployment of securement elements through wall 20 is a key part ofmany endoluminal procedures such as gastroplasty. For such securementelements to provide durable securement, they may need to be placedthrough the full thickness of stomach wall 20, including the outermostlayer, the serosa layer 22. It will be appreciated that the variablenature of rugae 30 makes the overall thickness of a given region ofstomach wall 20 relatively unpredictable. Therefore, to reliably deploya securement element via a tissue device from within the lumencompletely through organ wall 20 requires the securement element to bedeployed to a depth which takes into account the maximum thickness ofwall 20, which occurs when the maximum number and size of rugae 30 areencountered during deployment. As such, the deployment of suchsecurement elements may significantly overshoot the outer surface ofserosa 22, except in cases when the maximum thickness of wall 20 isencountered. Because damage to organs surrounding the stomach such asthe liver 500 and spleen 502 and puncture wounds to vessels such as thesplenic artery 504 may result in significant morbidity, it will beappreciated that consideration of such surrounding anatomy is ofparamount importance when penetrating an organ wall. Many aspects of thepresent invention relate to endoluminal procedures that are directed atminimizing this risk.

FIGS. 4 a and 4 b shows a depiction of a method and device for reducingthe risk described above. In FIG. 4 a a section of stomach wall isshown, along with an innermost wall, mucosal manipulation mechanism 508.For simplicity, stomach wall 20 is shown as a single layer plus therugae 30, without detailing the muscularis and serosa. Thissimplification is carried throughout most of the drawings disclosedhereafter. Mucosal manipulation device 508 comprises a pair of mucosalengagement mechanisms 510 having tissue engagement hooks 512. In atypical application of device 508, hooks 512 would be brought intocontact with the innermost wall layer, the mucosa 28, and then spreadapart to stretch out this layer, the rugae 30 and thereby leave asingle, flattened innermost wall layer of mucosa 28 adjacent device 508,as shown in FIG. 4 b.

In FIG. 5 a, a tissue device, in particular a tissue engagementmechanism 514 is shown pressed against the flattened innermost walllayer, the mucosa 28 created by the procedure shown in FIGS. 4 a and 4b. Mechanism 514 has a hook needle 58 mounted on a rotating element thatmay be a spur gear 68. When spur gear 68 is rotated, needle 58 isdeployed to selectively engage muscularis 24, as shown in FIG. 5 b. Theselectivity of the engagement of the layer adjacent the innermost layer,the muscularis 24 is the result of properly dimensioning hook needle 58in combination with the relative predictability of a single layer offlattened mucosa 28.

FIGS. 6 a and 6 b carry forth the elements shown in FIG. 5 b, with theaddition of an adjacent organ, the liver 500. In FIG. 6 b, mechanism 514has been moved into the lumen of stomach, pulling wall 20 along with it,and thereby creating a safety gap 7 between the outer surface of wall 20and liver 500. As shown, the depth and steepness of the sides of gap 7are such that the adjacent organ, the liver 500 does not conform with,and thereby fill in, gap 7.

FIGS. 7 a and 7 b carry forth the scenario shown in FIG. 6 b,illustrating the deployment of securement devices through wall 20 intothe gap 7. For purposes of clarity, mechanism 514 is not shown, but itwill be appreciated that it must maintain tension on wall 20 to sustaingap 7. FIG. 7 a shows curved suture needle 142 passing through the fullthickness of wall 20, into gap 7 and back into wall 20 withoutcontacting the liver 500. Similarly, FIG. 7 b shows a hollow needle 62passing through wall 20 and deploying a thread 64 having a T-anchor 90on its end.

FIG. 8 shows a trans-esophageal device 50 which is designed to performat least a portion of the methods described thus far, such methodsincluding manipulation of the innermost wall layer, the mucosa toflatten out its (rugal) folds, selective engagement of another walllayer, the muscularis, approximation of two regions of the stomach wall,pulling such approximated regions into the lumen to create a safety gap,and deploying a plurality of securement elements through theapproximated tissue regions to permanently secure them.

Device 50 is shown in FIG. 8 being inserted into a patient's stomach 10through esophagus 12. In the scenario shown, device 50 is insertedthrough an optional overtube 15, which would normally be inserted intoesophagus 12 first and would serve to shield the wall of esophagus 12from abrasion damage during the passage of a large instrument such asdevice 50. Device 50 may be attached to the end of a flexible endoscope46, in which case an auxiliary conduit (not shown) running from device50 alongside endoscope 46 and out the patient's mouth will be requiredin order to accommodate the multitude of control cables needed tooperate device 50. Flexible endoscopes typically have an access channel45, through which instruments can be passed, and user controls such assteering knobs, suction valves, insufflation, which are inferred by usercontrol block 47. It will be appreciated that device 50 may beconfigured as a stand-alone device, that is, not mounted onto anendoscope, in which case the user controls 47 and the auxiliary conduit(not shown) may be incorporated into a single device 50.

FIG. 9 shows a perspective view of trans-esophageal device 50, mountedon the end of endoscope 46. The device is configured with a roundedcylindrical shape having a top half 52 a and a bottom half 52 b, the twohalves meeting at seam 79, pivotally linked by hinge 54 and openablealong edge 56, shown in the closed state. Top half 52 a includes anarray of securement elements, in this case six suture deployment needles62, moveable together in carriage block 80, and an array of tissueengagement mechanisms moveable in carriage 66. Bottom half 52 b alsocontains an array of tissue engagement mechanisms moveable in carriage66, and has a needle catcher 81.

In the embodiment shown in FIG. 6, tissue engagement and drawingmechanisms in the form of hook-shaped needles 58 are shown. Asillustrated, a plurality of hook needles 58 may be mounted on spur gears68 which may engage a linear rack 70 which may be attached to anactuating wire 72. The hook needles 58 may be deployed by pulling thewire 72, thereby drawing the rack 70 upwards, and causing the spur gears68 to rotate (clockwise as shown) such that the needles 58 engage thetissue of a stomach wall 20. A release spring 74 is generally providedto bias the rack 70 in a direction to allow the hook needles 58 to beremoved from the stomach wall 20. Hook needles 58 preferably have asharp tip to penetrate the tough tissue of the muscularis, but agenerally flat body so as to engage the tissue without ripping throughit, after the needles have been deployed.

Hook needles 58 are mounted on carriage 66, which can be retractedtoward hinge 54 or advanced toward edge 56 by pulling on, or relaxing,wire 76. As will be described in more detail in FIGS. 13-18, byadjusting the position of carriage 66, the hook needles 58 canselectively engage the innermost wall layer, the mucosa 28 or the nextwall layer muscularis 24 of stomach wall 20. Once engaged, the carriage66 may be retracted into the cavity 60 of the device 50, thus capturinga portion of stomach wall 20 into the cavity 60. Device 50 is configuredto allow both top half 52 a and bottom half 52 b to capture portions ofstomach wall 20 with the two halves hinged apart, then to approximatethe two portions of stomach wall 20 as the halves are brought together.

Securement devices or tissue devices for securing the portions ofcaptured stomach walls 20 together are illustrated in FIG. 11. As shown,the device 50 includes a plurality of suture deployment needles 62 whichcomprise substantially hollow tubes configured to carry sutures 64. Thesuture needles 62 may be advanced by pulling on wire 86. In theembodiment shown, the suture needles 62 are held in a carriage block 80that incorporates an angled slot 83. A pin 84 attached to wire 86 isconfigured to travel in a constrained straight slot 88 (which isintegral to half 52 a) as well as in angled slot 83. As the wire 86 ispulled, pin 84 moves through straight slot 88, forcing angled slot 83 tofollow the path of pin 84 and thereby advancing the needle carriage 80toward the front edge 56 of device 50. Likewise, when wire 86 isreleased, needle carriage 80 is retracted by spring 76 disposed suchthat pin 84 will be biased towards the spring end of slot 88, therebycausing the needle carriage 80 to be retracted. Alternatively one ormore springs may be provided in different orientations and/or positionsin order to retract the suture needle carriage 80. Alternatively, one ormore retraction wires may be provided to allow a clinician to activelypull the carriage 80 in order to retract the suture needles 62 from thetissue. Still other pull wire and cam combinations may be employed toachieve the desired deployment of the suture needles 62. For example,the needle carriage 80 may comprise one or more wedge-shaped surfacesconfigured to engage a cam pulled by an actuating wire. Alternatively,each suture needle 62 may be located on an individual carriage block,thus allowing each needle 62 to be deployed individually if so desired.

With reference to FIG. 11 a, the securement device may comprise one ormore sutures 64 comprising T-anchors 90 and/or ball anchors 92 joined bya thread 94. The thread 64, T-anchors 90, and ball anchors 92 may bemade of any suitable bioabsorbable or biocompatible material available.Alternatively, staples or other slightly more rigid securement structuremay be used.

FIG. 12 illustrates an exemplifying arrangement of the hook needles 58,the hook needle carriage 66, the suture needles 62, and the sutureneedle carriage 80 as arranged in one of the device halves 52 a. It willbe appreciated that the number and arrangement of suture needles 62 isflexible, and may be adapted for a specific purpose. In the embodimentshown, the numbers of suture needles 62 were chosen to providereasonably close spacing of sutures along the segment of secured stomachwall tissue. The length of device 50, and thus the length of the securedsegment of stomach wall tissue, was chosen to be roughly the maximumlength which can be passed around the bend between the oral cavity andthe esophagus, which is generally between about 1.5 and 2.5 inches,depending on the shape of the device and the anatomy of the patient.Similarly, the diameter of device 50, in its closed configuration waschosen to be the maximum allowable through a typical esophagus, which isroughly between about 0.5 and 0.75 inches.

FIG. 13 is a section view taken through line A-A of FIG. 8 demonstratingthe initial positioning of device 50 in its closed position within thelumen of an organ, stomach 10. Device 50 as illustrated has beensimplified for clarity, showing only hinge 54, halves 52 a and 52 b, andcarriages 66. FIG. 13 a shows the position of distal-most spur gear 68and hook needle 58 on carriage 66 in relation to the front edge 56 ofdevice 50 in the arrangement shown in FIG. 13. As illustrated, carriage66 is slightly retracted and needle 58 is in its un-deployed position inthe configuration of the device as shown in FIG. 13.

FIGS. 14 and 14 a are identical to FIGS. 13 and 13 a, except the lumenof stomach 10 has been evacuated such that organ wall 20 is brought intoclose contact around device 50.

FIG. 15 shows the device 50 of FIG. 14 with hinge 54 opened and hookneedles 58 deployed to engage the innermost wall layer, the mucosa. FIG.15 a shows that carriage 66 is still slightly retracted and needle 58 isin its deployed position.

FIG. 16 shows the device 50 of FIG. 15 with hinge 54 closed and hookneedles 58 still engaging the mucosa, thereby stretching the mucosa 28over the body of device 50. FIG. 16 a shows that carriage 66 is stillslightly retracted and needle 58 is still in its deployed position. Theoperation shown in FIGS. 15 and 16 may be repeated multiple times toensure that all of the rugal folds 30 are substantially flattened in thevicinity of device 50. Although it is not shown, it will be understoodthat once halves 52 a and 52 b are closed and the mucosa 28 has beenstretched, hook needles 58 are refracted before halves 52 a and 52 b areopened again.

As an alternative to the method of flattening the rugal folds 30 asdemonstrated in FIGS. 15 and 16, device 50 may include one or moretissue manipulation mechanisms or tissue engaging members such as pawlteeth oriented such that as halves 52 a and 52 b are opened, the teethwill slide past the rugal rugae 30, but as the device 50 is closed, theteeth will engage the mucosa 28, thereby pulling the rugae 30 toward thefront edge 56 of the device 50. Alternatively, the device 50 may beconfigured such that the gripping and pulling action is performed as thedevice 50 is opened.

FIG. 17 shows the device 50 of FIG. 16 with hinge 54 once again open andhook needles 58 deployed to selectively engage another wall layer, themuscularis 24 of stomach wall 20. FIG. 17 a shows that carriage 66 hasbeen advanced to the edge 56 of device 50 so that when the needle isdeployed, as shown in FIG. 17 b, the stroke of needles 58 penetrate moredeeply into the wall, in the case shown into the muscularis.

FIG. 18 shows the device 50 of FIG. 17 with needles 58 still engagingthe muscularis 24 while carriage 66 is retracted, as shown in FIG. 18 a.In this way, a portion of the engaged segments of anterior and posteriorstomach wall 20 are pulled into cavity 60 of device 50, and a safety gap7 is created outside stomach wall 20.

FIG. 19 shows the device 50 of FIG. 18 with hinge 54 closed and halves52 a and 52 b brought together such that the engaged portions of stomachwall 20 are approximated. Note that safety gap 7 is further enhancedwith device 50 in the closed position. Also shown in the Figure areneedle deployment carriage 80 with needles 62, and needle catcher 81.Although not detailed elsewhere, it will be appreciated that needlecatcher 81 may be activated in the same manner, and at the same time as,deployment carriage 80.

As shown in FIG. 20, deployment carriage 80 is activated to push needles62 through the captured segments of stomach wall 20, whilesimultaneously needle catcher 81 is forced toward the bottom side of thecaptured wall 20 in order to receive the hollow needles 62 comingthrough wall 20.

FIG. 21 shows the completed securement procedure, with both thedeployment carriage 80 and needle catcher 81 having been retracted, andneedles 62 being captured by the needle catcher 81. As will be evidentby the combination of FIGS. 11 a and 21, as the hollow needles 62 passthrough the tissue and into needle catcher 81, an array of latches inneedle catcher 81 (not shown) engage notches 91 near the tips of each ofhollow needles 62, thereby allowing needle catcher to engage needles 62and pull them through the captured stomach wall 20. As this happens,each ball anchor 92 of suture elements 64 become anchored against thetop surface of the stomach wall 20 captured in half 52 a. When needlecatcher 81 is retracted, hollow needles 62 are pulled off of sutureelements 64, exposing T-anchors 90 and allowing them to become anchoredagainst the bottom surface of the stomach wall 20 captured in half 52 b.

In the manner illustrated in FIGS. 13-21, safe and reliable engagement,approximation and securement of two segments of an organ wall have beendemonstrated. FIG. 22 shows the resulting securement line 11, or luminalpartition, as seen from the outside of stomach 10. FIG. 22 a shows asection of stomach 10 from FIG. 22 taken along line 22 a-22 a.

The trans-esophageal device 50 and method for forming a gastric pouch 9provide a number of other advantages. Because the organ 10 is collapsedaround substantially the entire exterior surface of the device 50, theconfiguration of the luminal pouch 10 can be predetermined andcontrolled by the exterior shape of the device 50. This guarantees amore consistently sized pouch 9, reduces the need for visualization, andallows the minimally-invasive obesity treatment to be performedrelatively quickly and without the necessity of substantial amounts oftraining.

FIGS. 23-26 illustrate a two-step procedure for creating two luminalpartitions utilizing device 50. In FIG. 23, device 50 is positioned asshown to create a gastric partition, or securement line 11, in thelocation shown in FIG. 24. It will be understood that with device 50positioned toward the center of the lumen of stomach 10, the process ofstretching rugae 30 will not be exactly like that shown in FIG. 16,since in FIG. 16 device 50 is positioned with hinge 54 adjacent thelesser curvature 16 of stomach 10 and the length of stomach wall 20available for stretching closely matches the circumference of device 50.As such, in the case shown in FIG. 23, the stretching process willlikely take a few more iterations than in the case shown in FIG. 23.Nonetheless, a durable securement line 11 can be formed as shown in FIG.24 by following essentially the same steps as in FIGS. 13-21.

FIG. 25 shows the second step of the two-step process, wherein device50, after having been reloaded or replaced, is positioned above thesecurement line 11 formed during the first step, in a location similarto that shown for the procedure of FIGS. 13-21. As such, a secondluminal partition can be formed using the steps illustrated in FIGS.13-21. The resulting sets of two securement lines 11, as seen fromoutside the stomach 10, are illustrated in FIG. 26.

While a single securement line 11 extending from the Angle of His 32toward into the lumen of the stomach 10 can be useful in the treatmentof obesity and GERD, the two-partition arrangement shown in FIG. 26 ispreferable, since it creates more of a defined pouch space 9 with anarrow outlet 13 to restrict the outflow of material from pouch 9. Asdiscussed previously, adding a restrictive outlet to a luminal pouch maybe desirable in order to delay emptying of the pouch. In a stomach thismay sustain the feeling of fullness while restricting further foodintake.

Over time, pressure exerted by food against the walls 20 of the gastricpouch 9 will tend to permanently dilate the pouch 9. To minimize suchdilation, gastric pouch 9 may be modified by a variety of methods anddevices. For example, the muscularis 24 of the walls surrounding gastricpouch 9 may be altered by the application of thermal energy, causingshrinkage of the collagen fibers and an overall tightening of themuscle. Radio frequency (RF) energy may be applied directly to themuscularis 24 using needle electrodes or other electrode arrangements toaccomplish such shrinkage and tightening. Alternative ways of impartingthermal energy to the muscularis 24 without damaging the interveningmucosa 28 include, but not by way of limitation, applying microwaveenergy to the muscularis 24 and direct heating by electrically-heatedneedle tips that penetrate the muscularis 24. Still another process formodifying the walls of gastric pouch 9 consists of injecting of one ormore sclerosing agents into the muscularis 24 using an endoscopicinjection needle passed through the working channel of a flexibleendoscope, causing scarring and tightening of the muscularis 24.Examples of sclerosing agents that may be used include, but not by wayof restriction, detergent agents (e.g., Sodium Morrhuate, EthanolamineOleate, Sotradecol, Polidocanol, Scleremo), hypertonic and ionicsolutions (e.g., Hypertonic Saline, Sclerodex, Polyiodinated), andcellular toxins.

Additional ways to inhibit dilation of the gastric pouch 9 includemodifying the properties of the tissue lining the gastric pouch 9 by,for example, mechanically wounding the tissue (e.g., mucosectomy),surface chemical treatment (alcohols, alkyls, acids, etc.) of thetissue, ablating tissue or causing tissue necrosis using a tissuefreezing technique.

FIG. 27 illustrates a general approach to modifying the properties ofthe stomach wall 20 surrounding the gastric pouch 9 in order to minimizethe amount of dilation of the pouch 9. In the figure, an endoscopicaccessory 43 is deployed into the pouch 9 through the working channel ofa flexible endoscope 46. The accessory may be, for example, an injectionneedle, a cauterizing electrode, an argon plasma coagulator, a laser, amucosectomy snare, an RF electrode, a microwave antenna, or a cryogenicprobe.

In a variation of device 50, one or more pledgets may be deployed inconjunction with the activation of the securement function of device 50.With reference to FIGS. 11 and 11 a, a pledget 83 a may be loaded overeach needle 62 on the deployment carriage 80 such that when the sutures64 are deployed, a pledget 83 a will be trapped between the surface ofthe captured stomach wall 20 and ball anchor 92. Similarly, a pledgetcould be loaded on the top face of the needle catcher 81 and therebydeploy a pledget or pledgets 83 a which get trapped between the bottomface of the captured stomach wall 20 and the T-anchor 90. Using pledgets83 a with the securement devices in securing the stomach walls 20provides strain relief between the anchoring elements 90, 92 and thesurface of the tissue, thereby providing more durable tissue securementand preventing the securement line 11 from separating and the gastricpouch 9 from failing over time. Example pledget strips that may be usedare sold under the name Peri-Strips Dry® sold by Synovis SurgicalInnovations of St. Paul, Minn. Peri-Strips Dry® is composed of twostrips of biological tissue derived from bovine pericardium. However,other types of pledgets and other types of pledget material may be used,for example, but not by way of limitation, Teflon (ePTFE) pledgets maybe used. Pledgets 83 a may be made from any material available to thoseskilled in the art that is suitable for use in preventing the sutureanchors 90, 92 from abrading the tissue of the stomach wall 20. Forexample, resilient pledgets may also be used, such as a thin strip ofsilicone or thermoplastic elastomer (TPE) reinforced with stretchablewebbing such as nylon to provide tear resistance.

It may be desirable to cause wall-to-wall tissue adhesion or ingrowthsto create a more durable securement line 11. To facilitate this, atleast one segment of biocompatible material 310 may be disposed betweenthe layers of approximated tissue 240, 270. FIG. 28 shows a cutaway viewof a stomach that has been modified per the procedure illustrated inFIGS. 13-21, with the addition of a biocompatible material 310 extendingbetween the approximated layers 240, 270 of stomach wall 20. In theembodiment shown, the one or more segments of material 310 have beendeployed not only to promote wall-to-wall tissue adhesion or in-growthbetween the layers, but also to act as strain-relieving pledgets andthereby inhibit pull-through of the tissue securement devices 90, 92.

To promote wall-to-wall tissue adhesion or in-growth, the material 310is preferably porous enough to allow tissue in-growth, or may be formedwith holes or an open lattice structure to allow tissue to grow throughthe material. An exemplary material that may be used for this purpose isa polypropylene mesh, such as Marlex® mesh (CR Bard, Cranston, R.I.).

While it may be desirable from a durability standpoint to promote tissuein-growth between the approximated layers of stomach wall 20, thispresents a difficulty in reversing the procedure, since cutting throughthe ingrown tissue seam may present the risk of perforation of thestomach wall 20. As such, a further advantage of the embodimentillustrated in FIG. 28 is that the two-layers of material 320 shown maybe used as a guide in cutting through the in-grown segment of tissuewithout risk of perforation. To cut through the in-grown tissue, aseparation mechanism 320, which may be a thin, high-strength cuttingwire, can be moved in the direction of the arrow shown in FIG. 28 toseparate the one or more layers of material 310. The cutting wire may beenergized with cauterizing energy (radio frequency) to facilitate thecutting process and to provide coagulation of small vessels encounteredduring the cutting process. In an alternative embodiment, the element320 may be embedded or integrated into the one or more segments ofmaterial 310 to make it easier to perform the separation. Prior topledget separation or cutting with the pledget separation mechanism 320,tissue securement devices 90, 92 may be cut.

With reference to FIGS. 29 and 29 a, a gastric pouch 9 constructed inaccordance with an alternative embodiment of the invention will bedescribed. Instead of stomach walls 20 being directly secured to eachother along a securement line 11 to form the gastric pouch 9 discussedabove, the luminal pouch 9 may be formed by providing one or more stripsor pieces of material to form a partition 230 between walls 20 beingsecured together.

In the embodiment of the gastric pouch 9 shown in FIG. 29 b, thepartition 230 is secured to an invaginated tissue fold 240 of a firstwall 250 through one or more tissue securement devices 260 and issecured to an invaginated tissue fold 270 of a second wall 280 throughone or more tissue securement devices 290. In this embodiment, oppositewalls 250, 280 are separated or spaced from each other and partition 230thereby defines a portion of the gastric pouch 9. The partition 230 alsomitigates the possibility of the tissue of the stomach walls 250, 280adhering to one another after a period of time, making the proceduremore easily reversible (by just cutting through the material, forexample).

The partition 230 may be made from a variety of materials such as, butnot limited to, biological tissue, bovine pericardium, and Teflon(ePTFE). Alternatively, partition 230 may be made from a resilientelastic material that stretches if large volumes of food are forced intothe gastric pouch 9. In such an embodiment, the partition 230 creates a“shock absorber” effect that helps reduce tension on the tissuesecurement devices 260, 290, inhibiting the tissue securement devices260, 290 from pulling out of the tissue over time.

FIGS. 30-37 illustrate various embodiments of a trans-esophagealsuturing device 140 to safely and reliably administer endoluminaltherapy. The suturing device 140 illustrated in FIG. 30 is shownattached to the end of a flexible endoscope 46 by way of fastening ring158. Endoscope 46 is shown having an imaging lens 154, an air/waternozzle 155, illumination lenses 156, and a working channel 157. Inalternative embodiments, one or more of the imaging lens 154, theair/water nozzle 155, illumination lenses 156, and the working channel157 may not be present or may be incorporated into the device 140. Athroat 159 having a flexible section 161 and a device housing 150 extenddistally from the ring 158. The housing 150 of the suturing device 140generally has a substantially flat face 160, and a curved back 162, andalso includes a needle entry hole 164 and needle exit hole 166 throughwhich a semicircular needle 142 may pass. A slot 146 may be provided inthe housing to allow a suture thread 143 attached to the needle 142 topass between a needle path and the exterior of the device 140 as theneedle is cycled repeatedly through its substantially circular path.With reference to FIGS. 31 and 31 a, the tool 140 generally includes asemicircular needle 142 advanced by a needle driving mechanism 144.Needle 142 is driven by a swing arm 168 with a latching mechanism 170configured to engage a plurality of notches 172 formed in the needle142.

A typical stitch cycle will now be described with reference to FIGS.31-34. The suturing device 140 may be inserted into the stomach 10 of apatient with the needle 142 in the position shown in FIG. 33. In thisposition, the sharp ends of the needle 142 are held inside the devicehousing 150, thus preventing damage to the esophagus 12 or stomach 10during insertion of the device 140. Providing the needle 142 in thisposition also allows a clinician to visually align the needle 142 with amarked location for a suture stitch.

As shown in FIG. 33, the swing arm 168 is in a first position inpreparation for moving the needle 142. In order to move the needle 142,a clinician pulls on the pull wire 178 (see FIG. 35) causing the swingarm 168 to pivot about its axis 169 to the second swing arm positionshown in FIG. 34. The latching mechanism 170 engaged with the firstnotch 172 a will cause the needle 142 to be moved along with the swingarm 168 to the position of FIG. 34. As the pull wire 178 is released,the swing arm 168 will be returned to its first position shown in FIG.31. The lock pin 182 engaged with the fourth notch 172 d will preventthe needle 142 from being moved backwards by the swing arm 168.

Once a clinician is prepared to make a stitch, the pull wire 178 may bepulled again, thus causing the swing arm 168 to move to its secondposition while driving the needle 142 to the position shown in FIG. 32.From the position shown in FIG. 32, the swing arm 168 may again bereturned to its first position as shown in FIG. 33. The above steps maybe repeated as necessary to drive a plurality of stitches through astomach wall 20 or other tissue. As will be clear to those skilled inthe art in view of the present disclosure, the suture thread 143 willcontinue to extend through the slot 146 and out of the device housing150 throughout the stitching process.

With reference to FIGS. 31 and 31 a, the needle 142 of the embodimentshown generally includes first notch 172 a, second notch 172 b, thirdnotch 172 c, and fourth notch 172 d. The first notch 172 a and secondnotch 172 b are formed on an internal side 181 of the curvature spacedsuch that they will be engaged by the swing arm 168 to drive the needle146 through its circular path. The third notch 172 c and fourth notch172 d are positioned on portions of the needle 142 on an outside 183 ofthe curvature. The third notch 172 c and fourth notch 172 d willtypically be engaged by the spring-biased lock pin 182 in order toretain the needle 142 in the positions shown in FIGS. 33 and 31respectively as the swing arm 168 is moved between its first position(shown in FIGS. 33 and 31) and its second position (shown in FIGS. 34and 32) in order to continue advancing the needle 142.

As shown in the cut-away view of FIG. 35, the swing arm 168 is typicallymounted to a pinion spur gear 176 such that the swing arm 168 willrotate with the spur gear 176. A pull wire 178 may attached to a rockergear 180 which may be used to actuate the spur gear 176 in order to movethe swing arm 168. The gear ratio between the rocker gear 180 and thespur gear 176 is generally at least 2:1 in order to allow the swing arm168 to pivot through a full 180 degrees. In other embodiments, larger orsmaller gear ratios may be used, resulting in increased or decreasedpivoting range. The rocker gear 180 may be provided with teeth alongmore than 90 degrees in order to allow additional motion of the swingarm 168. The rocker gear 180 may be biased toward a first position by aspring or other biasing mechanism, or the rocker gear 180 may beprovided with a second pull wire to allow the rocker and thereby theswing arm 168 to return to a first position (as shown in FIG. 35).Alternatively, the needle 142 may be driven by one or more rollers,ratchet gears, or any other appropriate mechanism recognized as suitablefor driving the needle 142 about its circular path as shown anddescribed herein.

Needle 142 is typically made of stainless steel; however it may be madefrom any material suitable for use in surgical needles. The notches 172may be formed by any appropriate method. The radius of curvature, andthus the semi-circumferential length of the needle will typically bechosen to allow the needle 142 to pierce the outermost wall layer, theserosa layer 22 of the stomach 10 under assumptions of maximum wallthickness. The arc height 184 is indicated in FIG. 33 as the distancebetween the suture tool face 160 and the inner surface 181 of the needle(in the deployed position as shown). Of course, the thickness of stomachwalls 20 in humans tends to vary, however, studies indicate that astomach wall thickness of up to about 0.20 inches may be expected, andin one embodiment an arc height of up to about 0.22 may be used.

A suturing device such as that shown in FIGS. 30-37 could also beconfigured to drive two or more needles 142 spaced side-by-side orend-to-end. The particular orientations of the two or more needles 142may be chosen to suit the particular suture pattern desired.

The suturing device 140 may also be provided with mechanisms tomanipulate the mucosa 28, as is shown in the device 140 of FIG. 37,which includes rollers 196 configured to spread and flatten the mucosa28 in the area between the rollers 196 in opposite directions 199. Oncethe mucosa has been sufficiently stretched and flattened by the rollers,the hook needles 151 may be rotated away from one another to selectivelyengage the muscularis 24 of stomach wall 20 and hold the wall securelywhile a stitch is placed. Such engagement of the muscularis 24 alsoallows device 140 to pull stomach wall 20 into the lumen of the stomach10, creating a safety gap between the outer wall of the stomach andsurrounding structures, as was described previously. In the embodimentof the device 140 shown in FIG. 37, hook needles 151 may be actuated byany appropriate mechanism such as, by way of example only, a pull wire194 configured to pivot an axle 195 to which the needles 151 may beattached.

In an alternative embodiment of suturing device 140 illustrated in FIGS.38 and 39, corkscrew needles 152 are shown for temporarily securing oranchoring the device 140 to the stomach wall 20. In a preferred methodof use of this embodiment, the mucosa 28 is first smoothed or flattenedby either moving the arc of curved needle 146 across the mucosa 28, orinsufflating the lumen of the stomach 10 to the point where the mucosa28 and any rugae 30 are stretched out. Once the mucosa 28 issubstantially flat, the corkscrew needles 152 can be deployed to engagethe muscularis 24. In the embodiment shown, corkscrew needles 152 areconfigured to be rotated and thereby drawn into the tissue of thestomach wall 20 a sufficient depth that they engage the muscularis 24 ofthe stomach wall 20. Alternatively, the securing elements may comprisehook-shaped needles 151 (as shown in FIG. 37), barbed needles, suctionnozzles, or other devices sized and configured to at least temporarilyengage a portion of the stomach wall typically including at least aportion of the muscularis 24. The securing elements may be actuated byone or more push/pull wires attached to a belt, chain, cable etc. Thebelt, chain, or cable is generally configured to rotate the securingelements a desired amount in order to engage the stomach wall. Forexample, in the illustrated embodiment of FIG. 39, the securing elements152 are rotated by a toothed belt 190 which engages spur gears 192mounted to the securing elements 152. It will be appreciated that anyappropriate mechanism may alternatively be used to achieve the desiredtemporary securing of the device to the stomach wall 20. The securingelements are preferably sized such that they will not exit the serosa 22of the stomach 20, thus protecting the adjacent organs. In someembodiments, a penetration depth of about 0.06″ to about 0.10″ may besuitable, and in one embodiment, a depth of about 0.08″ is used. Thesecuring elements are typically spaced relative to the needle entry andexit holes 164, 166 such that the stomach wall tissue will be tightlyheld in the area to be sutured in order to allow the semicircular needle142 to penetrate to its desired depth through the stomach wall 20.

FIG. 33 a shows a variant of suturing device 140 incorporating anadjustable shim 153 on the face of housing 150. Assuming the device 140is kept in close contact with the mucosa 28, as by the securementelements discussed above, adjustment of shim 153 down or up willincrease or decrease, respectively, the depth of penetration of needle146. Adjustment of shim 153 may be done using a mechanism comprising atoothed belt 190 which rotates a series of screw elements that raise orlower the surface of shim 153.

In another aspect of the present invention, it may be desirable tomeasure the electrical impedance of the tissue in the vicinity of atissue-penetrating element. As discussed previously, such impedance datacan provide information about the depth of penetration, can provideconfirmation that the element has or has not penetrated the wall, andcan provide a warning that the element may have encountered an unwantedstructure such as a blood vessel.

Impedance sensing may be done using DC current or voltage but is morereliable when an AC current or voltage is passed between the electrodes(because of the electrolytic nature of biological fluids). Current-basedmeasurement is generally preferred because it fixes the amount ofcurrent regardless of how low the impedance gets. (In contrast,voltage-based impedance measurements can allow the current to increaseto levels that can cause tissue damage.) With an AC current impedancemeasurement circuit, the induced voltage is measured and then theimpedance is calculated. For low frequencies, the impedance is roughlyequal to the ratio of the voltage over the current. Higher frequenciescan be used for more precisely discriminating between specific tissuetypes by measuring the complex impedance of the tissue. These complexcomponents include both the capacitive and resistive factors, ratherthan only the resistive components that the low frequency or DCmeasurements determine.

FIG. 40 shows a basic impedance measurement system 519, consisting of anAC current source 516, a voltage measurement system 518, a firstelectrode 520, a second electrode 522, an impedance calculator 524, andan optional controller to automatically adjust the depth of penetrationof a securement element, such as a needle.

Impedance may be measured using either a monopolar or a bipolarapproach. FIG. 41 illustrates a monopolar embodiment of the suturingdevice 140 discussed above. In this illustration, the tip of needle 142functions as the first electrode 520, and an area on the surface ofdevice 140 serves as the second electrode. The needle swing arm 168makes electrical contact with the needle 142, and the swing arm 168 inturn is connected to a wire leading to an external impedance measurementsystem 519. In this embodiment, the tissue impedance is measured betweenthe tip of the needle and the electrode on the surface of device 140.

In a bipolar approach, the impedance is measured between two isolatedelectrodes in close proximity. As such, it tends to give a more accurateindication of impedance within a specific area. FIG. 42 presents anembodiment of a hollow needle 528 having two electrode areas 520, 522.Two corresponding electrode contact regions 530, 532 make electricalcontact with sliding contacts 534, 536, which in turn connect to anexternal impedance measurement system 519 through a pair of wires.

FIGS. 40 a and 40 b show exemplary graphs of impedance as the needleelectrode 146, 520 (shown in FIG. 41) is moved through the stomach wall.Initially, the impedance is infinite until the needle contacts themucosa 28, whereupon the impedance drops considerably. As it movesfurther into the muscularis 24, the impedance increase slightly, as thedistance between the first and second electrodes increase. When theneedle penetrates the serosa 22, the impedance again jumps to a veryhigh level, as shown in FIG. 40 a, unless the needle encounters a bloodvessel, which is highly conductive, as is depicted in FIG. 40 b.

FIG. 43 illustrates an application of the stitching device 140 describedabove. The stomach 10 is shown with a securement line 11 extending fromthe Angle of His 32 to more than halfway down the lesser curvature 16,forming a gastric pouch 9 that blends into an elongated tubular passagethat serves as a restrictive outlet 13 having a diameter D and length L.Such a procedure can be accomplished with the stitching device 140 byplacing a first stitch at the distal end of securement line 11,anchoring the suture with an anchoring device such as a knot or acrimpable anchoring element known to those skilled in the art, and thenplacing sequential stitches proximally until the securement line 11 iscomplete. It will be appreciated that the suture lines cannot be fullytightened until all of the stitches are placed, otherwise, the lumenwould collapse and make it difficult to use device 140. Thus, after thelast stitch is placed, a process of sequential tightening of thesutures, starting at the distal end and working proximally, can beemployed. Once tightened, the proximal end of the suture can beanchored.

The restrictive outlet 13 formed by the procedure depicted in FIG. 43has unique properties. First, because it is bordered by the lessercurvature 16, it is less likely to dilate over time than if it wereformed elsewhere in the stomach 10. Second, because of its length, it islikely that any such dilation that does take place will occur only atthe proximal end of the passage, where the pressure of food being forcedinto the passage is the highest. By the time the food makes it throughthe passage, the radial forces exerted on the passage will be minimal,so the distal portion of the passage will remain relatively stable.

Another important facet of the restrictive outlet 13 shown in FIG. 43 isthat the restrictive effect can be modified by changing the length ordiameter of the passage. Specifically, by lengthening the passage ornarrowing the diameter by adding pleats along a wall of the passage(using endoluminal tools similar to those described previously), therestrictive effect increases. In contrast, by shortening the passage orincreasing the diameter, the restrictive effect is lessened. As such,this form of restrictive outlet 13 may be used as an adjustablerestrictive outlet 13 the effect of which can be modified over time bysimple endoscopic adjustments (such as adding or cutting stitches).

FIG. 44 illustrates another technique for creating a restrictive outlet13 to a gastric pouch 9. A mucosal bunching device 538 which isgenerally egg shaped, has a distal anvil 540, an interior space 539 intowhich mucosa 28 is sucked using suction applied through vacuum ports542, a radial array of staples 544 and a staple pusher 546. By deployingdevice 538 into the outlet of a gastric pouch 9 and applying suctionthrough ports 542, mucosa 28 is sucked into the stapling space, and thestaples are then pushed through the mucosa and formed against the anvil.In doing so, the mucosa acts a natural flow restrictor to the flow offood out of pouch 9.

To make the technique shown in FIG. 44 more robust, a generally circularshaped pledget may be deployed by the bunching device 538 during thestapling procedure. Many variations of such circular pledgets are shownin FIGS. 45 a-j. In certain embodiments, such as those shown in FIGS. 45g-j, and adjustment thread 680 is incorporated, allowing the restrictiveoutlet to be cinched up or loosened by the clinician endoscopically.

Yet another approach to creating a restrictive outlet 13 to a gastricpouch 9 is shown in FIG. 46, wherein an endoscopic injection needle 549is shown injecting pockets of a bulking agent between the mucosa 28 andthe muscularis 24. A number of appropriate bulking agents are known tothose skilled in the art, including, but not limited to, those derivedfrom natural tissue, for example human and animal collagen, muscle, fatand cartilage, and those derived from synthetic materials, such assilicone, polymethylmethacrylate, polyethylene, polypropylene,polypropylene, Delrin, and Teflon. Such materials may be bioreactive, inthat their properties change once implanted, as in the case ofexpandable hydrogels, ethyl vinyl alcohol and water-swellable polymers.Such bulking agents may be injectable as in the case of a solution,suspension, slurry or paste, and may be combined with a carrier toassist with injection or to enhance biocompatibility. Alternatively, thebulking agent may be inserted in a pre-formed shape, as in the case of asponge, expandable hydrogel prosthesis or bladder.

Still another combination of a device and method for creating a gastricrestriction is shown in FIGS. 47-53 a. In FIG. 47, a side section viewof a device 552 similar to device 50 described previously is shown,having analogous elements including hinge 54, case halves 52 a and 52 b,tissue engagement mechanisms 66, a tissue securement deployment carriage80 and needle catcher 81. In FIG. 48, device 552 is shown in the lumenof stomach 10 with tissue engagement mechanisms 66 engaging the mucosa28. In FIG. 49, hinge 54 is opened, causing the spreading of mucosa 28and rugae 30. This spreading procedure may be carried out iterativelyuntil the mucosa is adequately flattened. In FIG. 50, hinge 54 of device552 is fully opened and hooks 151 are deployed to engage the muscularis24. Once the muscularis 24 has been engaged, hinge 54 closes, bringinghalves 52 a and 52 b together and pulling an invaginated fold of stomachinto the cavity of device 552. Securement carriage 80 is then deployed,pushing a needle 62 (not shown) carrying a suture 64 (not shown) similarto that shown in FIG. 11 a is pushed through the top of invaginated fold554. FIG. 52 depicts the completed procedure showing suture 64 andanchor elements 90 and 92 securing the fold.

When the procedure illustrated in FIGS. 47-52 is combined with astitching procedure similar to that shown in FIG. 43, the outcome isshown in FIGS. 53 and 53 a. As can be seen in FIG. 53, a gastric pouchand restrictive outlet are formed, similar to that in FIG. 43. However,as illustrated in FIG. 53 a, the invaginated fold 554 is trapped in thelumen of restrictive outlet 13, creating a natural and highly effectiverestrictive to flow.

It will be appreciated that dilation of the restrictive outlet 13 overtime is a concern and that the same techniques described herein forminimizing the dilation of the gastric pouch 9 can be applied to therestrictive outlet 13.

Although certain embodiments and examples have been described herein, itwill be understood by those skilled in the art that many aspects of themethods and devices shown and described in the present disclosure may becombined differently and/or modified to form still further embodiments.Additionally, it will be recognized that the methods described hereinmay be practiced using any device suitable for performing the recitedsteps. Such alternative embodiments and/or uses of the methods anddevices described above and obvious modifications and equivalentsthereof are intended to be within the scope of the present disclosure.Thus, it is intended that the scope of the present invention should notbe limited by the particular embodiments described above, but should bedetermined only by a fair reading of the claims that follow.

1. A method of reducing the flow of material or fluid through a segmentof a stomach cavity, comprising: trans-orally forming a gastric pouchwithin the stomach cavity segment, at least a portion of the pouchpositioned adjacent and along a section of the Lesser Curvature of thestomach so material or fluid entering the stomach cavity segment ispassed through the pouch; and after forming the pouch, trans-orallyforming a restriction one of within and adjacent to the pouch to reducethe flow of material or fluid through the stomach cavity segment.
 2. Themethod of reducing the flow of material or fluid through a segment of astomach cavity of claim 1, wherein a portion of the pouch is near thestomach's Angle of His.
 3. The method of reducing the flow of materialor fluid through a segment of a stomach cavity of claim 1, whereintrans-orally forming the gastric pouch within the stomach cavity segmentincludes: trans-orally employing a tissue engagement assembly to engageat least two target regions of the stomach cavity wall; and trans-orallyemploying a tissue securement assembly to secure the at least two targetregions to form at least a section of the gastric pouch.
 4. The methodof reducing the flow of material or fluid through a segment of a stomachcavity of claim 1, wherein trans-orally forming a restriction one ofwithin and adjacent to the pouch includes trans-orally employing arestriction formation device assembly to apply one or more securementelements to tissue one of within and adjacent to the pouch.
 5. Themethod of reducing the flow of material or fluid through a segment of astomach cavity of claim 1, wherein trans-orally forming a restrictionone of within and adjacent to the pouch includes trans-orally employinga restriction formation device assembly at multiple tissue locations oneof within and adjacent to the pouch to apply one or more securementelements to the tissue locations.
 6. The method of reducing the flow ofmaterial or fluid through a segment of a stomach cavity of claim 4,wherein the securement elements includes one of sutures and staples. 7.The method of reducing the flow of material or fluid through a segmentof a stomach cavity of claim 1, wherein trans-orally forming the pouchwithin the stomach cavity segment includes: inserting a device assemblytrans-orally at least partially into the stomach cavity segment, thedevice assembly including a tissue engagement assembly and tissuesecurement assembly; evacuating the stomach cavity segment to collapseregions of the stomach cavity wall about the device assembly;trans-orally employing the tissue engagement assembly to engage at leasttwo target regions of the stomach cavity wall; and trans-orallyemploying the tissue securement assembly to secure the at least twotarget regions to form at least a section of the pouch.
 8. The method ofreducing the flow of material or fluid through a segment of a stomachcavity of claim 1, wherein trans-orally forming a restriction one ofwithin and adjacent to the pouch includes: trans-orally employing arestriction formation device assembly to draw tissue one of within andadjacent to the pouch into the restriction formation device assembly;and trans-orally employing the restriction formation device assembly toapply one or more securement elements to the drawn tissue in order toform the restriction.
 9. The method of reducing the flow of material orfluid through a segment of a stomach cavity of claim 8, whereintrans-orally employing a restriction formation device assembly to drawtissue one of within and adjacent to the pouch into the restrictionformation device assembly includes applying a vacuum through the lumenof the restriction formation device assembly to draw tissue one ofwithin and adjacent to the pouch into the restriction formation deviceassembly.
 10. The method of reducing the flow of material or fluidthrough a segment of a stomach cavity of claim 9, wherein the vacuumdraws multiple tissue regions into the restriction formation deviceassembly and securement elements are applied to the multiple drawntissue regions.
 11. The method of reducing the flow of material or fluidthrough a segment of a stomach cavity of claim 9, wherein the vacuumdraws multiple tissue regions into a radial suction cavity of therestriction formation device assembly and a staple array is applied tothe multiple drawn tissue regions.
 12. The method of reducing the flowof material or fluid through a segment of a stomach cavity of claim 3,wherein the stomach wall includes tissue layers and an innermost tissuelayer lines the stomach cavity, wherein trans-orally forming the pouchwithin the stomach cavity segment includes: manipulating the stomach toreduce one of the size and number of folds of the innermost tissue layerat or near the at least two target regions so the innermost tissue layeris substantially flat at or near the at least two target regions;engaging the at least two target regions along the stomach wall aftermanipulating the innermost tissue layer folds at or near the at leasttwo target regions; and securing the engaged at least two target regionstogether to form at least a section of the pouch.
 13. The method ofreducing the flow of material or fluid through a segment of a stomachcavity of claim 1, wherein the pouch has an inlet and an outlet, whereinthe pouch inlet is formed at or near the stomach's Angle of His and therestriction is formed at or near the pouch outlet.
 14. The method ofreducing the flow of material or fluid through a segment of a stomachcavity 1, wherein the reduction of the flow of material or fluid throughthe stomach cavity segment provides treatment for one of obesity andgastroesophageal reflux disease.
 15. The method of reducing the flow ofmaterial or fluid through a segment of a stomach cavity 1, wherein thereduction of the flow of material or fluid through the stomach cavitysegment temporally extends a feeling of fullness within the stomachcavity.